Electric water heater



Feb. 2 1926.

w. A. SHARPE ELECTRIC WATER HEATER Filed Oct. 23, 1924 gwuento'c .5Mil/am Jbaqoe.

Patented Feb. 2, 1926.

UNITED STATES PATENT OFFICE.

ELECTRIC WATER HEATER.

Application filed October 28, 1924. Serial 1T0. 745,860.

To alt whom it may concern:

Be it known that I, WILLIAM A. SHARIE, a citizen of the United States,residing at the city and county of Denver and State of Colorado, haveinvented certain new and useful Improvements in Electric Water Heaters;and I do declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawings, and to the charactors of reference markedthereon, which form a part of this specification.

This invention relates to electric heaters for use in heating water.

In our present state of civilization, we are in constant need of hotwater for a variety of purposes, and many difierent arrangements havebeen rovided for heating water conveniently, wit the result that nearlyall homes have a supply of hot water available for immediate use. It isevident that the sim lest and most convenient way of producing heat isby means of an electric current, as such a source of heat is clean,odorless and easil controlled.

It is the ob ect of this invention to produce an electric heatingelement that shall be especially well adapted for heating water, andwhich can be used as an instantaneous water heater to provide hot waterfor any purpose, but especially for baths.

It is a further object of this invention to produce an automaticpressure-operated switch that will close the electric circuit when wateris drawn and to open the same when the water ceases to flow. When mheater is to be used in connection with shower baths, the switch may bemechanically connected to the handle and so related therewith that thecircuit to the heater will be closed whenever the valve is opened andwill remain closed as long as water is rmitted to flow through thevalve, but w ich will open the circuit whenever the valve is closed.

It is a still further object of this invention to roduce a heater inwhich the Water shaill have a long ath on which it is constantlysubjected to eat from the electric resistance so that there will be aneliicient transfer of heat to the water.

The above and other objects that will ap- {gear as the descriptionproceeds, .are obtained y means of a construction which I shall nowdescribe in detail, reference for this purpose being had to theaccompanying drawings in which the referred embodiment of my inventionis lllustrated, and in which:

Fig. 1 is a view showing my improved heater, partly in elevation andpartly in section;

Fig. 2 is a side elevation of the arts shown in Fig. 1 with a partthereof s owng a section taken on line 22, Fig. 1;

Fig. 3 is a view taken along line 33, Fig. 5. and shows the switchelement partly in section showing the switch in open position;

Fig. 4 is a view similar to that shown in Fig. 3 and shows the switch incircuit-closing position;

Fig. 5 is a section taken on line 5-5, Fig. 6, and shows one way ofconnecting the switch to the heater; and

Fig. 6 is a view showing my heater connected to a shower bath.

My improved heater is preferably formed from two substantially identicalporcelain members 1 and 2 of rectangular shape. Each one of thesemembers is provided. at opposite ends with semi-cylindrical projectinglugs 3, which when in assembled position, forms a c lindrical openin forthe reception of the bushing 4. This ushing has an outwardly projectingflange 5 that eooperates with a correspondinggroove in the insidesurfaces of parts 3 for the purpose of holding the bushing againstlongitudinal movement. A zig-zag semi-circular groove 6 extends from oneend openin to the other and when the parts are assem led, forms acircular opening for the resistance element 7 that is formed into anelongated helix which is put under sufiicient tension to keep theadjacent coils out of contact. A oove 8 extends around the porcelain memre 1 and 2 and serves for the reception of a suitable packing. Each ofthe members 1 and 2 have lugs or ears 9 that are rovided with openingsfor the reception 0 .the bolts 10, by means of which the parts are heldin aasembled position. One end of the resistance coil 7 is-connected tothe binding post 11 and the other end is connected by means of the strip12 with the binding post 13. Secured to the bushing 3 at the upper endof the heater is a T 14. To the upper end of the T, I secure a fittingdesignated by numeral 15. This has a cylindrical opening 16 for thereception of the piston 17 that is movably mounted therein. A rod 18 isconnected at its lower end to the piston and is slidably associated withthe guides 19 and 20. A spring 21 surrounds themed 16 and abuts its endagainst the underside of the guide lug 19 and the nut 22. This spring isunder compression and tends to move rod 18 and piston 17 downwardlyagainst the pressure of the water. It may be remarked here that thelower bushing is connected to the water supply and the side opening 23of the T is connected to the discharge faucet (not shown). When thefaucet is closed, the pressure to which the piston 17 is subjected isequal to the'full pressure of the water supply. When the faucet is openand the water is flowing, the piston it subjected to a greatly reducedpressure. The tension of the spring is so adjusted by means of the nut22 that it will move the piston 17 downwardly to the position shown inFig. 1 when the water flows and move it upwardly substantially to thetop of the piston chamber when the faucet is closed. I utilize themovement of the rod 18 for the purpose of opening and closing a switchthat controls the current to the resistance coil. As an example of aswitch mechanism that can be used for this purpose, I have shown a bentswitch arm 24 that is pivoted at 25 to member 26 from which it isinsulated. A contact 27 is located in the The rod 18 is provide with twocollars spaced a short distance apart. The end 29 of the lever 24projects between the collars 28. It is now evident that when the rod 18moves upwardly as when the water exit is closed, then the arm 24 will berotated clockmatically connected and disconnecte occasion requires.

wise about its pivot, which movement will cause the end thereof to moveaway from the contact 27. When the faucet is opened the pressure towhich the piston is sub ected will immediatel decrease and the switchwill close the circuit to the resistance element, which will then becomehot and heat the water. The switch mechanism described above isillustration only and I contemplate employing a sna switch in lieuthereof, preferably a doub e pole tumbler type.

It is evident from the above description that I have reduced a heater ofa neat and pleasing design that can readily be connected 'in a watersupply to a bathroom or sink and which will instantaneously heat wateras it.

is required, the electric energy bein autoas the (path of the arm 24.

When the heater is to be employed in connection with a shower bath, Iprefer to substitute for the automatic switch one that is controlled bythe valve and in Figs. 3 to 6 I have shown such an arrangement. Thevalve 30 is preferably of the plu is operated by the handle 31. gecuredto the rotating plug is a sheet of insulating material 32 to which atubular member 33 of insulating material is connected. The meanber 33 isprovided with metal-conducting caps 34 to which terminals 35 and 36 areconnected. The terminal designated 36 is longer than terminal 35 and isspaced therefrom by a short gap. A quantity of mercury 37 is containedin the tubular member. When the valve is closed the member 33 ishorizontal and the mercury is out of contact with either terminal, butwhen the valve is moved to open position the mercury bridges the gapbetween the terminals in the manner shown in Fig. 4. The mercury switchjust described is connected in series with the resistance element,somewhat as shown in Figs. 5 and 6. When the valve is closed, thecircuit is broken, but just as soon as the valve is opened, the circuitis closed and the heater becomes effective. The temperature of the watercan be regulated by means of the valve 30. If the valve is opened only asmall amount, the water will be hot and as the rate of flow isincreased, the temperature decreases. The zigzag shape of the grooves 6and the resistance element 7 is of great importance in this combination,as it 'ves a long passage without unduly increasing the size of theapparatus.

Particular attention is called to the combination shown in Figs. 1 and2, as it produces a sim le self-contained device that requires mere y tobe properly connected to a water and an electric current supply tofunction properly.

aving now described my invention, what I claim as new is:

1. An electric water heater, comprising, in combination, twocomplementary, substantially flat plates of insulating material each ofwhich is provided with a groove extending in a zig zag path from one endto the other, each of said coves having a substantially semi-circulzlrcross-section, said grooves being so related that when the plates areplaced so that the grooved sides are placed face to face, the grooveswill register so as to form a cylindrical zig za opening, a helicalresistance member in sai o enings, means for securing said plates togetier and exposed terminals electrically connected with the resistancemember.

2. An electric water heater, comprising in combination, twocomplementary, substantially flat plates of insulating material, each ofwhich 18 provided with a groove extendinginazigzagpath from oneendtothetype and other, each of said grooves having a substansaid section, meansfor securing said plates tially semi-circular cross-section, saidgrooves together, a helical resistance member in said 10 being sorelated that when the plates are zigzag opening and exposed terminalselecplaced so that the grooved sides are placed trically connected tothe ends of the said 5 face to face, the grooves will register so asresistance member.

to form a cylindrical zig zag opening, said In testimony whereof I aflixmy signature.

opening terminating at opposite ends of said plates in an enlargedsection, a bushing in WILLIAM A. SHARPE.

